Characterization Of Phenolic Compounds Research Articles

Up-Cycling Grape Pomace through Sourdough Fermentation: Characterization of Phenolic Compounds, Antioxidant Activity, and Anti-Inflammatory Potential.

Despite its appealing composition, because it is rich in fibers and polyphenols, grape pomace, the major by-product of the wine industry, is still discarded or used for feed. This study aimed at exploiting grape pomace functional potential through fermentation with lactic acid bacteria (LAB). A systematic approach, including the progressively optimization of the grape pomace substrate, was used, evaluating pomace percentage, pH, and supplementation of nitrogen and carbon sources. When grape pomace was used at 10%, especially without pH correction, LAB cell viability decreased up to 2 log cycles. Hence, the percentage was lowered to 5 or 2.5% and supplementations with carbon and nitrogen sources, which are crucial for LAB metabolism, were considered aiming at obtaining a proper fermentation of the substrate. The optimization of the substrate enabled the comparison of strains performances and allowed the selection of the best performing strain (Lactiplantibacillus plantarum T0A10). A sourdough, containing 5% of grape pomace and fermented with the selected strain, showed high antioxidant activity on DPPH and ABTS radicals and anti-inflammatory potential on Caco2 cells. The anthocyanins profile of the grape pomace sourdough was also characterized, showing qualitative and quantitative differences before and after fermentation. Overall, the grape pomace sourdough showed promising applications as a functional ingredient in bread making.

LC-ESI-QTOF-MS/MS Characterization of Phenolic Compounds in Common Commercial Mushrooms and Their Potential Antioxidant Activities

Mushrooms have a long history of use as food and medicine. They are rich in various nutrients and bioactive compounds, particularly phenolic compounds. In this study, ten mushroom species were selected, and solvent extraction using 80% ethanol was used to extract phenolic compounds. Total phenolic content (TPC), total flavonoid content (TFC) and total condensed tannin content (TCT) were measured to evaluate phenolic content in different mushroom varieties. In the mushroom varieties tested, brown portobello mushroom had the highest TPC (396.78 ± 3.12 µg GAE/g), white cup mushroom exhibited the highest TFC (275.17 ± 9.40 μg CE/g), and shiitake mushroom presented the highest TCT (13.80 ± 0.21 µg QE/g). Antioxidant capacity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), 2,2′-azino-bis-3ethylbenzothiazoline-6-sulfonic acid (ABTS) and total antioxidant capacity (TAC) assays. The highest DPPH free radical scavenging ability was found in white cup mushroom (730.14 ± 55.06 µg AAE/g), while the greatest iron-reducing ability (FRAP) was recorded for shiitake mushroom (165.32 ± 10.21 μg AAE/g). Additionally, Swiss brown mushroom showed the highest ABTS antioxidant capacity (321.31 ± 5.7 μg AAE/g), and the maximum TAC value was found in shiitake mushroom (24.52 ± 1.2 μg AAE/g). These results highlight that most of the mushroom varieties studied showed high phenolic contents and demonstrated strong antioxidant activity, with shiitake mushrooms standing out due to their high TCT and FRAP values, and the highest TAC value among the varieties studied. In addition, LC-ESI-QTOF-MS/MS was used to characterize the mushroom samples, and tentatively identified a total of 22 phenolic compounds, including 11 flavonoids, 4 lignans, 3 phenolic acids, 2 stilbenes and 2 other phenolic compounds in all mushroom samples. The research results of this study showed that mushrooms are a good source of phenolic compounds with strong antioxidant potential. The results can provide a scientific basis for the development of mushroom extracts in functional food, health products, and other industries.

Rheum turkestanicum and R. ribes: Characterization of phenolic compounds and a LCESI-QqTOF MS based comparison with the officinal Chinese rhubarb, R. palmatum

The limited supply of Chinese officinal rhubarbs (Rheum palmatum L., R. tanguticum Maxim. ex Balf., and R. officinale Baill.) has resulted in the use of other Rheum species in many places. Therefore, investigating the metabolite profile of unofficinal rhubarbs, and an analytical comparison of their metabolite profile with the officinal ones is crucial. Rheum turkestanicum Janisch. and R. ribes L. are two Rheum species distributed in Iran and are widely being traded in traditional markets as substitutes for R. palmatum. Herein, we isolated different phenolic compounds in the roots and rhizomes of R. turkestanicum and R. ribes by chromatographic techniques and identified them by nuclear magnetic resonance spectroscopy (NMR), electronic circular dichroism (ECD), electrospray ionization-mass spectrometry (ESI-MS), and high-resolution mass spectrometry (HRMS). In addition, the metabolite profile of the two above-mentioned species were compared with that of R. palmatum by liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry (LC-ESI-QqTOF MS). The obtained MS data were statistically compared by non-metric multidimensional scaling (NMDS) and analysis of similarities (ANOSIM) and a heatmap was plotted for comparing the tested samples. The isolated compounds were catechins, anthraquinones, naphthoquinones, chromones and rhododendrol glycosides, among which (-) 3′,4′′-di-O-methyl-catechin-3-O-gallate was a new compound. The results of LC-MS/MS analysis indicated that while catechins were the most abundant compounds in R. ribes, anthraquinones and naphthalenes were the main constituents of R. palmatum and R. turkestanicum. Interestingly, the substitution in the hexosyl residue of anthraquinone and naphthalene hexosides was a malonyl or an acetyl group in R. palmatum, while this substitution was a 3-hydroxy-3-methylglutaryl group in R. turkestanicum. This may be considered as a potential marker for the differentiation of R. palmatum and R. turkestanicum. The statistical analysis showed that R. palmatum, R. turkestanicum, and R. ribes are distinct species, however, R. turkestanicum had some similarities to R. palmatum. In conclusion, R. turkestanicum can be a subject for future phytochemical, pharmacological, and clinical research regarding its ability to be used as a potential substitute for R. palmatum in pharmaceutical industries.

Extraction and Analytical Characterization of Phenolic Compounds from Brazil Nut (Bertholletia excelsa) Skin Industrial by-Product

Pressurized liquid extraction (PLE) and ultrasound assisted extraction (UAE) were applied to extract phenolic antioxidants from defatted Brazil nut skin (DBNS) industrial by-product. Water/alcohol solvents (ethanol and methanol) (0 - 50 % v/v water) were used at temperatures of 50 - 200 °C in PLE and 50 °C was set in UAE. The effect on extraction yield, total phenolic compounds content (TPC), antioxidant capacity and phenolic characterization was determined. The temperature and water/alcohol mixture affected the dielectric constant, and this in turn influenced the yield, TPC, antioxidant activity and phenolic composition. In PLE, at 200 °C and 50 % (v/v) water/alcohol (ethanol and methanol) the highest yields (33.8 and 38.4 %, respectively), TPC (4673 and 5435 mg GAE/100 g DBNS) and antioxidant capacity (397 and 502 µmol TE/g DBNS) were obtained. Furthermore, at 50 °C, PLE had better extraction efficiency than UAE. Characterization of the extracts indicated that at 50 - 100 °C the extraction of protocatechuic acid and ellagic acid derivative were predominant, while at 150 - 200 °C catechin and vanillin derivatives stand out. In general, hydroxybenzoic acids and flavonoids were the most abundant phenolics, and the addition of 25 % v/v water to ethanol resulted in extracts with their highest concentration. Then, Brazil nut skin is an interesting phenolic-rich source with potential use to produce bioactive ingredients. HIGHLIGHTS High temperature and water/alcohol mixtures improves TPC and antioxidant capacity At given temperature, TPC values are linearly correlated with water/alcohol dielectric constant Extraction temperature modifies the abundance and profile of phenolic compounds Hydroxybenzoic acids and flavanols are predominant phenolics in Brazil nut skins At 50 °C, PLE have a better extraction efficiency of phenolic compounds than UAE GRAPHICAL ABSTRACT

Characterization of Phenolic Compounds of Olea europaea L. and Ceratonia siliqua L. Leaf Extracts by HPLC-ESI-MS

Background: Olive (Olea europaea L.) and carob (Ceratonia siliqua L.), which contain considerable amounts of phenolic compounds, are the most important nutritional and therapeutic plants in the Mediterranean basin. Objectives: The goal of this work is to revalue carob and olive leaves as key sources of polyphenols, hence increasing the value of waste goods. Methods: In this study, aqueous acetone or ethanol (80% v/v) extracts of olive (O. europaea L. cultivar aimel) and carob (C. siliqua L.) leaves from Algeria were evaluated for phenolic content, and the extracts were characterized by reverse-phase high-performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS). Discussion and Results: The total phenolic content of olive and carob leaf extracts ranged from 5.6 to 23 mg GAE/g. The use of HPLC-ESI-MS to investigate phenolics revealed that the extracts included a variety of phenolic compounds, including 23 compounds in olive leaf extracts and 17 compounds in carob leaf extracts. In olive and carob, the major phenolic components are oleuropein and myricetin rhamnoside, respectively. Conclusion: According to our findings, olea europaea and Ceratonia siliqua appear to be rich suppliers of natural chemicals. These plants have a lot of potential in terms of medications and functional foods.

LC-ESI-QTOF-MS2 Characterization of Phenolic Compounds in Different Lentil (Lens culinaris M.) Samples and Their Antioxidant Capacity.

Lentil (Lens culinaris M.) is a legume widely consumed worldwide. It is rich in bioactive compounds, including polyphenolic compounds that contribute to positive health benefits. This study aimed to determine the phenolic content and antioxidant activity of black, red, green, and brown whole lentils. Towards this end, the lentils' phenolic compounds were evaluated regarding their total phenolic content (TPC), total flavonoid content (TFC), total tannin content (TTC), total condensed tannin (TCT), total proanthocyanin content (TPAC), total anthocyanin content (TAC). For the antioxidant activity 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), hydroxyl radical scavenging activity (•OH-RSA), ferrous ion chelating activity (FICA), reducing power assay (RPA) and phosphomolybdate (PMA) assay were accessed. To identify individual phenolic compounds, liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS2) was used. The results showed that green lentils exhibited the highest TPC (0.96 mg gallic acid equivalents (GAE)/g) whereas red lentils presented the highest TFC (0.06 mg quercetin equivalents (QE)/g). Black lentils were noted with the highest TCT (0.03 mg catechin equivalents (CE)/g), TPAC (0.009 mg cyanidin chloride equivalents (CCE)/g), and TAC (3.32 mg/100 g) contents. While the greatest TTC (2.05 mg tannic acid equivalents (TAE)/g) was observed in the brown lentil. Regarding the total antioxidant capacity, red lentils (4.01 mg ascorbic acid equivalents (AAE)/g) presented the greatest activity, whereas the lowest was found in the brown samples (2.31 mg AAE/g). The LC-ESI-QTOF-MS2 tentatively identified a total of 22 phenolic compounds, containing 6 phenolic acids, 13 flavonoids, 2 lignans, and 1 other polyphenol. The relationships among phenolic compounds by Venn Diagram showed a high number of overlapping compounds in brown and red lentils (6.7%), and a low number of overlapping compounds between the green, brown, and black lentils (2.6%). Flavonoids were the most abundant phenolic compound within the studied whole lentils, with the brown lentils being the richest in phenolic compounds, especially flavonoids. This study emphasized a comprehensive understanding of the antioxidant potential of lentils and disclosed the phenolic distribution across various lentil samples. This may increase interest in the development of functional food products, nutraceutical ingredients, and pharmaceutical applications with lentils.

Screening and characterization of phenolic compounds by LC-ESI-QTOF-MS/MS and their antioxidant potentials in papaya fruit and their by-products activities

Papaya (Carica papaya L.) is one of the most commonly planted and consumed fruits in the world, especially in tropical and subtropical areas. In recent years, due to the diverse range of nutritional value and medicinal properties of bioactive substances possessed in papaya, papaya fruit and their by-products have gained more attention. The present study aimed to characterize the different parts (pulp, peel, and seed) of two varieties of papaya (yellow- and red-fleshed) at different stages of ripeness (unripe and ripe) for their phenolic compounds using liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS). The phenolic content and antioxidant activity were detected through several assays. Yellow-fleshed unripe papaya seed showed the highest total phenolic content (TPC) (4.73 mg GAE/g). Red-fleshed ripe papaya peel exhibited the highest level of total tannin content (TTC) with 1.98 mg CE/g, while red-fleshed unripe peel exhibited the highest total flavonoid content (TFC) with 2.78 ± 0.04 mg QE/g. In terms of antioxidant potential, yellow-fleshed unripe papaya peels had the highest radical scavenging activities for the DPPH, ABTS, and TAC tests. LC-ESI-QTOF-MS/MS experiment successfully tentatively identified 118 phenolic compounds in total, including phenolic acids (35), flavonoids (61), stilbenes (3), lignans (7) and other polyphenols (12) in all papaya samples. Analyses indicate that the three different parts of the papaya fruit are potential sources of phenolic compounds, particularly the peel. The results of this study provide practical data for the potential application of papaya fruit as a functional food ingredient in the food, pharmaceutical and medicinal industries.

Antioxidant, Antimicrobial Activities, and Characterization of Phenolic Compounds of Thyme (Thymus vulgaris L.), Sage (Salvia officinalis L.), and Thyme–Sage Mixture Extracts

The antioxidant properties of sage (Salvia officinalis L.) and thyme (Thymus vulgaris L.), and their mixtures were examined using the 2,2-Diphenyl-1-picrylhydrazyl (DPPH•) scavenging activity and ferric-reducing activity of plasma (FRAP) methods. The antimicrobial activity of the plant extracts against four bacterial strains (Escherichia coli, Staphylococcus aureus, Bacillus cereus, and Salmonella typhomorium) was determined using the agar well diffusion method. Results showed the highest overall rate of increase in total phenolic (13.67 mg·GAE/g·DW), and flavonoid (6.75 mg·QUE/g·DW) contents in the thyme–sage mixture extract compared with the thyme and sage extracts. As found by GC-MS analysis of methanolic extracts, thymol, apigenin, rosmarinic acid, and carvacrol were the most abundant phenolic compounds in the thyme–sage extract. The lowest EC50 (DPPH•, 55.51 μg·ml−1) and the highest FRAP value (95.51 mM Fe (II) mg−1 extract) were recorded in the extract of the thyme–sage mixture compared with sage and thyme extracts, and butylated hydroxytoluene solution (BHT). The highest antimicrobial activity against E. coli, S. aureus, B. cereus, and S. typhomorium was observed in the thyme–sage mixture with the inhibition zone diameters of 22.13, 28.67, 31.25, and 23.65 mm, respectively. It is concluded that the extract obtained from the thyme–sage mixture has more potential to be used in the pharmaceutical and food industry as a natural antibacterial and antioxidant agent.

Heliotropium procubens Mill: Taxonomic Significance and Characterization of Phenolic Compounds via UHPLC-HRMS- In Vitro Antioxidant and Enzyme Inhibitory Activities.

The aim of the present study was the phytochemical analysis of the aerial parts of Heliotropium procumbens Mill., a herb from Boraginaceae plant family not previously studied. The methanol (ME) and aqueous extracts (WE) of the aerial parts were assayed for their total phenolic and flavonoid content and antioxidant properties, using free radical scavenging (DPPH, ABTS), reducing power (FRAP, CUPRAC), phosphomolybdenum and metal chelating assays. The extracts displayed considerable free radical scavenging activity against DPPH and ABTS radicals, with potential values of 46.88 and 68.31 mg TE/g extract for ME, and 93.43 and 131.48 mg TE/g extract for WE, respectively. Key clinical enzymes involved in neurodegenerative diseases AChE and BChE, diabetes (α-amylase and α-glucosidase) and skin whitening (tyrosinase) were also assayed. The phytochemical profile of the studied species was determined through UHPLC-HRMS, whereby 26 secondary metabolites were identified, three of which (luteolin-7-glucoside, lithospermic and rosmarinic acids) were isolated and structurally determined by NMR spectral means. H. procubens was found to harbor bioactive metabolites and could, hence, serve as a source of biological activities which could be further explored and exploited for potential applications.

Extraction and characterization of phenolic compounds with antioxidant and antimicrobial activity from avocado seed (Persea americana mill)

The increase in the demand for Hass avocado has brought a rise in the generation of inedible waste such as peel and seed, by-products that are rich in bioactive substances. In the present study, aqueous, ethanolic, and supercritical fluid extracts were obtained from fresh seed and dry seed, which were analyzed to determine the antioxidant capacity measured through 2,2-diphenyl-2-picrylhydrazyl free radical (DPPH); 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC) methods as well as the content of phenolic compounds. In addition, the antimicrobial activity of strains of food interest, such as Listeria monocytogenes, Salmonella enterica Typhimurium and Escherichia coli was evaluated. The ethanolic extract of fresh seed presented the highest antioxidant and antimicrobial activity. The aqueous extract of fresh seed registered a significant antioxidant capacity but an absence of antimicrobial activity. In contrast, the ethanolic extract of dry seed showed a representative antimicrobial activity on both S. enterica Typhimurium and L. monocytogenes, but low antioxidant activity. E. coli exhibited resistance against all the assessed extracts. The results from this work highlight the opportunity to consider the Hass avocado seed extracts as a novel alternative to replace or reduce the use of synthetic antioxidant and antimicrobial additives in food. Keywords: Waste by-product; Aqueous extract; Ethanolic extract; Supercritical extraction; Polyphenols; Free radical.

The characterization of phenolic compounds via LC-ESI-MS/MS, antioxidant, enzyme inhibitory activities of Salvia absconditiflora, Salvia sclarea, and Salvia palaestina: A comparative analysis

Salvia L. genus, one of the medicinal and aromatic plants belonging to the Lamiaceae family, is represented by many endemic species in temperate regions worldwide. The Salvia species have plenty of usages in traditional medicine, important pharmacological effects and economic value. In this context, this study was conducted to evaluate the chemical profile and potential bioactivity of ethyl acetate extracts from 3 different Salvia species; Salvia absconditiflora (Salvia cryptantha- an endemic species), S. sclarea and S. palaestina collected from different localities in Anatolia. Total phenolic-flavonoid contents, antioxidant properties and enzyme inhibition experiments were investigated in tested Salvia species. The phenolic profiles were also determined by liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The analysis revealed the presence of phenolic compounds in ethyl acetate extracts such as cynaroside, rosmarinic acid, cosmosiin, luteolin, apigenin and acacetin. The highest level of phenolic components was detected in S. absconditiflora with 74.16 mg GAE/g. The best radical scavenging and reducing abilities were found in S. absconditiflora (DPPH: 251.39 mg TE/g; ABTS: 340.16 mg TE/g; CUPRAC: 496.20 mg TE/g; FRAP: 322.94 mg TE/g). Moreover, the inhibition of AChE, BChE, and α-amylase has also been studied. The most potent AChE inhibitory ability was recorded in S. sclarea (4.00 mg GALAE/g), followed by S. palaestina (3.38 mg GALAE/g) and S. absconditiflora (3.01 mg GALAE/g). The extracts exhibited similar amylase inhibitory effects. These results reveal that Salvia species [S. absconditiflora (S. cryptantha), S. sclarea and S. palaestina] confirming their potential can be rich sources of promising bioactive compounds as a starting point for further analysis. In addition, it is thought that this study may be the new report for the construction of helpful databases in terms of shedding light on future research and researchers with the valuable information obtained about these economically important Salvia species.

Effect of aqueous leaf extract of Macaranga barterion selected haematological and biochemical indices of carrageenan -induced paw edema in Wistar albino rats

This research was designed to determine the anti- inflammatory and quantitative characterization of phenolic compounds in aqueous leaf extract of Macaranga barteri on carrageenan induced paw edema in wistar rats. Phenolic compound was characterize using GC-MS. Twenty wistar rats of both sexes weighing between 120-140g were grouped into 5 with four (4) rats per group. Group 1 served as the normal control which received distilled water, group 2 (negative control) rats received 1% carrageenan only, groups 3 and 4 were treated with aqueous leaf extract of M. barteri, group 5 was treated with diclofenac, 30 minutes after receiving 1% carrageenan, the changes in paw sizes were observed hourly for 3 hours. Rats were sacrificed and blood samples collected for haematological and biochemical analyses. Phenolic compounds detected were 2-nitro phenol (3.29 ppm) and 4-chloro-3-methyl-phenol (5.09ppm). Significant reduction in rat paws oedema was observed when rats in group 4 were compared with group 2 at 3hours with percentage oedema inhibition of 46.91. Mean ESR of rats in groups 2, 3 and 5 significantly increased and group 4 none significantly reduced when compared to control. Non-significant differences in mean WBC, neutrophil and lymphocyte counts, significant reduction of mean eosinophil counts in groups 2 and 3 and non-significant increase in group 4 when compared to control. Significant increase in mean CRP concentration was observed when group 2 was compared to control group and a significant reduction in group 4 treated with 500mg/kgb.wt. When compared to group 2. Mean concentrations of Il-6 and prostaglandin significantly increased in all the groups when compared to control. Aqueous leaf extract of M. barteri demonstrated near average percentage paw oedema inhibition and mild anti-inflammatory potential at 500mg/kg b.wt.

Argentinian Sugar Cane Vinasse: Characterization of Phenolic Compounds and Evaluation of Adsorption as a Possible Remediation Technique

Chemical composition of sugar cane vinasse (Tucumán, Argentina) was studied finding high concentration of organic compounds. Phenolic compounds were partially characterized, finding mostly flavonoids, anthocyanins, as well as resorcinol and ferulic acid derivatives. Adsorption isotherms of phenolic compounds and total organic compounds were measured on four commercial activated carbons with different physical and chemical properties at two temperatures. The isotherm shape depends on the type of carbon and the adsorption capacity is enhanced as temperature increases. Enthalpies of the adsorption process were estimated, revealing that the adsorption of organic compounds is a chemisorption process, while the adsorption of phenolic compounds is a physisorption process on three of the tested carbons and a chemisorption process on the other one (CONCARBO).

High hydrostatic pressure assisted by food-grade enzymes as a sustainable approach for the development of an antioxidant ingredient

Apple is one of the most important fruits in the world. The elaboration of apple-based products such as cider or apple juice generates around 3–4.2 million tonnes of apple by-product that are annually discarded. Apple by-product has been described as an interesting source of bioactive compounds, including polyphenols. These valuable components, once extracted, could enable the usage of the apple by-product as a natural antioxidant ingredient. The aim of the present work was to address the effect of high hydrostatic pressure (HHP), and HHP assisted by two alternative food-grade enzymes, Celluclast®, and Ultraflo®. For that purpose, the total phenolic content was measured by Folin-Ciocalteu and Fast-Blue BB assays. Furthermore, antioxidant capacity was determined by three analytical methods (DPPH, ORAC and FRAP) and the characterization of phenolic compounds was carried out by Chromatography and Mass Spectrometry analysis. Results indicated a significant increase of the total phenolic content and the antioxidant capacity after the HHP aided by Celluclast® or Ultraflo® treatment. Conversely, the exclusive application of HHP induced minor changes. Thus, the combination of HHP and the food-grade enzymes Celluclast® or Ultraflo®, has proved to be an effective strategy for the extraction of natural antioxidant compounds from the apple by-product.

Functional food obtained from fermentation of broccoli by-products (stalk): Metagenomics profile and glucosinolate and phenolic compounds characterization by LC-ESI-QqQ-MS/MS

This research revalues broccoli stalk by-product as a novel fermented health food, using its autochthonous microbiota. Broccoli stalk slices were packed into glass jars, brine was added (6% w/v), and two dressings were studied: garlic, and mustard seeds. No dressing was used as control. Natural fermentation was carried out at 25 °C for 6 days followed by a further 6 days storage at 4 °C. The identification of individual glucosinolates and phenolic compounds was performed by LC-ESI-QqQ-MS/MS. At day 3, the highest content in functional compounds such as glucoerucin and indolic glucosinolates as glucobrassicin, 4-methoxy-glucobrassicin and 4-hidroxy-glucobrassicin, and phenolic acids and flavonoids as sinapic acid, 4-O-feruloyl quinic acid and quercetin-3-O-diglucoside was found. At day 6, the broccoli stalks reached the maximum counts in lactic acid bacteria (>8 log cfu g−1), remaining stable until day 12 at 4 °C, including as the main genera Lactobacillus and Leuconostoc. Metagenomic analysis identified 1009 bacteria genera; Latilactobacillus sakei was the most predominant lactic acid bacteria species, followed by Lactobacillus curvatus, Leuconostoc kimchi and Leuconostoc carnosum. This is an example of a vegan and functional food product, based on a circular economy model, using broccoli by-products.

Insight into Isolation and Characterization of Phenolic Compounds from Hawthorn (Crataegus pinnatifida Bge.) with Antioxidant, Anti-Acetylcholinesterase, and Neuroprotective Activities.

Recent epidemiologic studies have demonstrated a link between the consumption of daily functional fruits rich in phenols and the prevention of disease for neurodegenerative disorders. Hawthorn products are derived from the functional fruit hawthorn, which is rich in phenols and has been used around the world for centuries. In order to explore the phenolic components in hawthorn, the investigation of the ethanol extract led to the separation of five new phenol compounds (1a/1b, 2-4), including one pair of enantiomers (1a/1b), along with seven disclosed analogs (5-11). Their structures were elucidated based on extensive spectroscopic analyses and electronic circular dichroism (ECD). The compounds (1-11) were tested for antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonicacid) (ABTS), and ferric reducing antioxidant power (FRAP) methods. Apart from that, monomeric compounds 2, 4, and 6 exhibited more potent protective capabilities against H2O2 (hydrogen peroxide)-induced SH-SY5Y cells. Meanwhile, electronic analyses were performed using the highest occupied molecular orbital (HOMO), and the lowest unoccupied molecular orbital (LUMO) to analyze compounds 2, 4, and 6. Furthermore, compounds (1-11) measured acetylcholinesterase (AChE) inhibitory activities, and 2, 4, and 6 possessed greater AChE inhibitory activity than donepezil. At the same time, molecular docking was used to investigate the possible mechanism of the interaction between active compounds (2, 4, and 6) and AChE.

Characterization of phenolics and discovery of α-glucosidase inhibitors in Artemisia argyi leaves based on ultra-performance liquid chromatography-tandem mass spectrometry and relevance analysis

Artemisia argyi leaves (AAL) has been widely used as herbal medicine and food supplement and in China and other Asian countries. The aim of this work is to qualitative and quantitative characterization of phenolic compounds in AAL and screening of natural product inhibitors of α-glucosidase from AAL. Ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF-MS) was employed to rapid and comprehensive identification of phenolic compounds in AAL, and a total of thirty-three phenolic compounds were identified. High performance liquid chromatography with diode array detection (HPLC-DAD) was established and validated to simultaneously determinate ten main bioactive phenolics compounds in different batches of AAL samples. Meanwhile, the inhibitory capacities of different batches of AAL samples on α-glucosidase were evaluated. Then, relevance analysis, including grey relational analysis and Pearson correlation analysis were employed to investigate the correlations between the contents of phenolic compounds and α-glucosidase inhibitory activities, and discover the α-glucosidase inhibitors in AAL. The relevance analysis results indicated that three phenolic compounds, 3-caffeoylquinic acid, 3,4-dicaffeoylquinic acid and 3,5-dicaffeoylquinic acid could be potential α-glucosidase inhibitors in AAL. Moreover, the α-glucosidase inhibitory activities of the three phenolic compounds were validated by in vitro and in vivo experiments. The possible inhibiting effect of the three phenolic compounds on α-glucosidase was also explored by molecular docking analysis, and the results indicated that the binding of the three α-glucosidase inhibitors to α-glucosidase mainly by hydrogen bonds, hydrophobic forces and ionic bonds. The present research provided a deep insight into phenolic compounds and α-glucosidase inhibitory activities of AAL, and discovered the α-glucosidase inhibitors in AAL.

Impact of Provenance on Phytochemical Attributes of Pigmented Landrace Maize Varieties

Maize is one of the most diverse cereal crops that contribute highly in calorie supply to human diet. Pigmented maize secondary metabolites which are phytochemicals of healthy importance include carotenoids and phenolics which act as precursors of vitamin A and antioxidants respectively. Pigmented landrace maize is cultivated by smallholder farmers in their localities. Three different pigmented maize varieties from different growing districts were analysed for total carotenoids content (TCC) and total phenolic content (TPC), using spectrophotometer. The districts experience a warm temperate climate and higher rainfall in summer than in winter but they differ in that Ntcheu has highest average annual temperature of 20.3°C while Dedza receives the highest annual precipitation of about 1010 mm. Mzimba has an average annual temperature of 20.1°C and receives about 915 mm of precipitation annually. Individual carotenoids were analysed using high performance liquid chromatography (HPLC). TCC were significantly higher (p < 0.05) in Ntcheu and Mzimba provenances compared to Dedza. Lutein (22.84 ± 1.25 µg/g) and Zeaxanthin (23.16 ± 2.44 µg/g) were highest in landrace orange maize from Ntcheu. Mzimba provenance showed highest beta-cryptoxanthin (8.60 ± 2.15 µg/g). TPC were not significantly different between Dedza (204.29 ± 0.35 mg/Kg) and Mzimba (207.65 ± 0.22 mg /kg) red maize. Ntcheu provenance showed the least TPC (184.06 ± 0.61 mg/Kg). It seems provenance influenced phytochemical attributes of pigmented landrace maize varieties in some instances. This study also revealed that post-harvest handling of pigmented landrace maize affects phytochemical content. Care should, therefore, be taken in handling pigmented landrace maize to avoid phytochemical loses. Farmers and all other stakeholders in Malawi are encouraged to produce and include pigmented landrace maize varieties in their diets in order to gain the associated health benefits. Further studies are needed for complete characterisation of phenolic compounds of pigmented landrace maize of Malawi.

Studies of Phenolic Compounds Coupled to Minerals in Cocoa Beans of the “Mercedes” and “Forastero” Varieties from the Divo and Abengourou Regions (Côte d’Ivoire)

The aim of this study is to contribute to the valorization of the cocoa bean varieties “Mercedes” and “Forastero” grown in Côte d’Ivoire. A comparative characterisation of phenolic compounds and minerals in the beans of the “Mercedes” and “Forastero” varieties from two major cocoa production areas of Côte d’Ivoire were determined. The phenolic compounds of cocoa beans were determined by high performance liquid chromatography (HPLC) and the minerals by atomic absorption spectrophotometer. The study showed that a significant difference at the 5% level was observed in the averages of minerals, cinnamic acid, protocatechic acid, quercetin, coumaric acid, rutin, ellagic acid, veratric acid, epicatechin, ferulic acid and naringenin. On the other hand, no significant difference at the 5% level was observed in the averages of arbutin, catechin, vanillic acid and caffeic acid in the bean kernels analysed in the Divo and Abengourou regions. The proportion of cinnamic acid is (6.18±0.63 mg/100g “Mercedes” Divo), that of ellagic acid is (18.48±0.44 mg/100g “Mercedes” Divo) and that of naringenin is (5.95±0.35 mg/100g “Mercedes” Divo). The amount of potassium is (7569.97±1.51 mg/kg “Forastero” of Abengourou) and that of iron is (179.9 ± 0.70 mg/Kg “Forastero” of Divo). The phenolic compounds and minerals in the cocoa bean samples analysed are highly correlated and rich in antioxidants. They would be beneficial for many biological functions. They can be recommended in pharmacology and cosmetics to fight against oxidative stress and cardiovascular diseases.

Characterization of phenolic compounds, sterols and geographical fingerprint of Memecik extra-virgin olive oils according to their geographical locations by using LC IMS QTOF Mass Spectrometry

Characterization of phenolic compounds, sterols and geographical fingerprint of Memecik extra-virgin olive oils according to their geographical locations by using LC IMS QTOF Mass Spectrometry